Dalton's atomic theory postulated that 'Atoms combine in simple whole-number ratio'. What are the postulates of modified Dalton's atomic theory?

List the drawbacks of Dalton's atomic theory.

Dalton's atomic theory says that atoms are indivisible, Is this statement still valid? Give reason in support of your answer.

What is an atom? How do atoms exist?

Why is it not possible to see an atom even under a powerful microscope?

Is it possible to see atoms? Explain your answer.

What is meant by the symbol of an atom? Explain with the help of examples.

State the guidelines for writing the symbols of different elements.

Give five symbols which have been derived from the 'English names' of the elements. Give their English names also.